Automatic electric fire-alarm



No Model.) Y

L. G. WOOLLEY.

- AUTOMATIC ELECTRIC FIRE ALARM. No. 471,929. I Patented Mar.29,1892.

- Uivrrnnv STATES PA ENT Orr cn.

LEONIDAS-IG. WOOLLEY, on GRAND RAPIDS, incl-near.

AUTOMATIC ELECTRIC FIRE-ALARM,

\ $PECIIIGATIONfor ning paid; of Letters Patent No. 471,929, dated March 29, 1892.

Application tiled December 1;, 1891. Serial No. 414,929.-,'(No model.)

To all whom it may concern.-

Be it known that I, LEONIDAS WooLLnY,

' of Grand Rapids, in the county of Kent and State of Michigan, have invented certain new and useful Improvements in Automatic Electric l lre-Alarms; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use it, reference being had to the accompanying drawings, which form part of this specification.

My invention relates to improvements in automatic electric fire-alarms; and it consists in the combination, construction, and ar rangement of parts, which will be fully described hereinafter, and particularly referred -to in the claims.

I-Ieretofore electric fire-alarms have been constructed with electric contact-points in the circuit of a battery for closing the circuit automatically by the effect of heat and sounding an alarm. Alarms of this character are very defective, however, from the fact that the batteries become dried up and inoperative when they are needed or become inoperative from one or more numerous causes to which they are subjected, thus failing to sound an alarm when the contact-points are operated to close the circuit thereof. On the other hand theyare liable to fail to sound an alarm from the reason that-the contact-points in the course of time become corroded, oxidized, or dirty and will fail to close tlie circuit when operated for that purpose. For these reasons the ordinary electric fire-alarms are very defective, and these defects '1 ogrcrcome in my alarm. g

The object of my invention. is to produce an'automatic electric fire-alarm constructed to suddenly and automatically separate a magnet and armature, one of which is provided with an induction-coil when the temperature of the room or building in which it is placed has reached any prescribed degree,

whereby a momentary current is produced in the induction-coil for sounding an alarm at a central station or other place through. linewires connected therewith, thus doing away with abattery and electriccontacts so liable.

to be out of order when a fire occurs, thus avoiding the defects of an ordinary electric fire-alarm.

In the drawings, Figure 1 is a side elevation of a fire-alarm which embodies my invention and 3 are similar views I complete. Figs. n showing modifications. Fig. 4 is a detached view showing a modification of the destructible or fusible device. Fig. 5 is a view of a modified form showing the armature stationary and magnet removable.

A indicates an L-shaped bracket or support,

which is secured within a roomor building at any desired point, but preferably to the cciling. Secured to this bracket and depending therefrom is a permanent magnet B, prefer: ably of the horseshoe type, which has 'two poles or arms of unequal length, the arm 0 eing here shown the longest, though this spcoi-flclconstruetion may be reversed, if desiredlor the arms made of equal length, as

will appear farther on. Where the magnet is formed as shown in Fig. 1, an inductioncoil L is placed on the longer arm 0, which has its opposite ends connected withlinewires connected with an electric indicator of any desired construction, which is placed at a centralstation or otherplace where it is desired to sound an alarm. Y

'lhe armature E is held to the poles of the magnet by magnetism and is L-shaped to ex tend to the long and short ends thereof. A

leverI is pivoted near the inner ends to adepending arm ll of the bracket A. The long end of this lever engages anoteh made in the upper end of a thermostatic bar J, whilea weight G is suspended upon the short end thereof. This thermostatic bar is composed of dissimilar metals, the expansion of one being greater than that of the other, so that if the temperature of the room or building is v raised the bar J bends in the. direction inditure E, so that the dropping of-the weight suddenly removes the armature from the magnet, thus producing a momentary current by induction in the coil L, which sounds an electric alarm to be connected therewith. The arinatu reE is connected with the bracket by means of a chain 1), which prcven ts it and the weight'from becoming detached from the device when they drop.

By making one end of the magnet longer than the other the coil L can be wound thereon by placing the magnet in a lathe, thus reducing the cost of winding the magnet, while at the same time the inner coils of the induction-coil can be wound tightly thereon, thus intensifying the current OVGI that produced when the coil is wound and then slipped thereon. When the two arms of the magnet are of the same length, the coils must be first wound and then slipped thereon, or it wound directly thereon must be wound by hand, thus increasing its cost.

In Fig. 2 I show a modified form of releasin g device, which consists of a fusible hook. M, upon which the weight is suspended. \Vhen the temperature has raised sufficiently to fuse the hook, the weight drops and causes a current in the same manner as shown in Fig. 1.

In Fig. 3 I show a pivoted armature E and a magnet 13', the arms of which are of the same length, though one arm may be shorter than the other and the armature correspondingly shaped, if desired. I here show a springactuatcd lever, which is held set by means of a fusible block I), placed between its freeend and a pin (1, or the pin cl itself maybe made fusible. In this case, when the block or pin is fused the spring-actuated lever is released, which strikes the free end of the armature, moving it suddenly from the poles of the magnet, creating a momentary current in the induction-coils L.

Another modification of the releasing device is shown in Fig. 4, which consists of a glass ball f, which is filled with gases which will explode the ball when the temperature of the room or building has reached a certain degree, thus releasing the spring-lever a for striking the armature and moving it from the magnet.

From the above description it will be seen that I do not limit. myself to any particular kind of magnet-releasing device or means for suddenly 1' ,:ieasing the armature, for any one or all of these may be varied to any desired degree without departing from the spirit otmyinvcntion, wizbh comprises a magnet; having an armature, a storcdnp power for suddenly releasing it, and a thermostatic trip for releasing the power.

lly means of an alarm of this character all danger of its becoming inoperative from inattention, corroding, or oxidizing, or the lapse cl time is entirely overcome, as will be und d-stood, thus producing a simple and cheap .1 alarm witlmut the serious defects usually at ii Ailing devices olthis character.

a mlaethe induction-coil oi vcryfinc wire,

w i't'ibl current of very high ciectromotor naling apparatus,

force is obtained over that compared with the current produced by a battery. For instance, I can use a wire so fine that a momentary curreiit of high voltage is obtained, to pl'OtlllUO which by a battery would require a great number of cells. The induction coil or helix has its terminals permanently connected to a suitable electro-magnet in a sigthe purposeot the electromagnet being simply to momentarily release an. armature or tripping device in a large mechanical gong actuated by weights or springs, as the current generated by a single sudden removal of the armature from the magnet c poles is but momentary and too feeble to direclly operate a bell-striker. It will now be understood that the coil or helix of insulated wire to be brought under influence of the permanent magnet by the sudden removal of its armature is placed in a permanentlyclosed circuit with the signaling apparatus, the current necessary to operate the entire system being produced wholly by md uction from apermanent magnet. All circuit-closing devices and batteries are entirely dispcnscd with. Owing to this fact Iain enabled to use smaller conductors than can be used with a battery and at the same time produce a surer result with a corresponding lessening of expense.

While I here show the induction coil or coils placed upon the magnetic poles, it may be placed upon the armature, as shown in Fig. 5, and the same result produced. So, also, in either case the armature may be permanently held and the magnet itself suddenly removed therefrom, as shown in Fig. 5, the result being nearly the same.

Having thus described my invention, what I desire to claim and secure by Letters Patent is 1. An automatic electric fire-alarm comprising a permanent magnet, an armature therefor, an induction-coil, a stored power for suddenly separating the armature and magnet, and athermostatic releasing device, substantially as specified. g

2. An automatic electric fire-alarm comprising a permanent magnet, an armature therefor, an induction coil or helix in a permanentlyclosed circuit with a signaling apparatus, a stored power for suddenlyseparating the armature and magnet, and a thermostaticreleasing device, substantially as set forth.

ICC

An automatic electric fire-alarm comprising a permanent magnet, an armature therefor, an induction-coil, a. means for suddenly separating the armature and magnet to produce a momentary current in the coil, and a thermostatic holding and releasing device holding the means until the temperature affeets it sulliciently to release it, substantially as specified.

4-. An electric lire-alarm comprising a permanent magnet, an armature therefor, an induction-coil, a weight connected with the armature, and a thermostatic device for holding and releasing the weight, substantially as set forth.

Y 5. An automatic electric fire-alarm comprising a magnet carrying a coil, an armature therefor, a weight connected with the armature, a pivoted lever supporting the weight;

. and a thermostatic device for holding and releasing the lever, substantially as specified.

6. An automatic electric fire-alarm comprisinga magnet carrying an induction-coil, an

armature therefor, a weight connected with the armature, a pivoted lever supporting theweight,'anda strip composed! of dissimilar metals, having one end permanently held and its opposite free end engaging the said "lever, I 5

In testimony whereof I aifix my signature in :0

presence of two witnesses.

LEONIDAS G. WOOLLEY.

Witnesses: I

ALL-EN S. PATTISON, HEATH SUTHERLAND. 

